qubit

noun

qu·​bit ˈkyü-bət 

plural qubits

: a unit of computing information that is represented by a state of an atom or elementary particle (such as the spin) and can store multiple values at once due to the principles of quantum mechanics

And the most basic truth of quantum mechanics dictates that you cannot measure a qubit without destroying the superposition. The register that said 1 and 0 will randomly collapse into 1 or 0.

—George Johnson

compare bit entry 3 sense 1

Examples of qubit in a Sentence

Recent Examples on the Web

Quantum computers can generate and control qubits to perform computations. —Britney Nguyen, Quartz, 22 Jan. 2025

However, Google’s researchers discovered a way to reduce errors by introducing more qubits to a system and were able to correct them in real time. —Emma Roth, The Verge, 9 Dec. 2024

Our co-doping approach further enhances this, allowing for more qubits without degrading performance. —New Atlas, 30 Nov. 2024

Another cornerstone of quantum mechanics is entanglement, where qubits become interconnected. —Jason Snyder, Forbes, 9 Jan. 2025

Word History

Etymology

qu- (in quantum entry 2) + bit entry 4, probably formed with punning allusion to cubit

Note: According to the American physicist Benjamin Schumacher, in the acknowledgements to a paper ("Quantum coding," Physical Review A, vol. 51, issue 4 [April, 1995], p. 2747), "The term 'qubit' was coined in jest during one of the author's many intriguing and valuable conversations with W. K. Wootters, and became the initial impetus for this work."

First Known Use

1994, in the meaning defined above